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arXiv 1802.08574math.LO
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分形测度棱镜下的强测度零集和弱可加集

Strong measure zero and meager-additive sets through the prism of fractal measures

Ondrej Zindulka

摘要:

我们发展了一个与Borel的\emph{strong measure zero}相似的\emph{sharp measure zero}集理论,并证明了一个类似于Galvin-Myscielski-Solovay定理的定理,即一个实数集有锐测度零当且仅当它是弱可加的.一些后果:$2^ω$的子集是弱可加的当且仅当它是$\mathcal E$ -可加的;如果$f:2^ω\to2^ω$是连续的并且$X$是弱可加的,那么$f(X)$也是。

英文摘要:

We develop a theory of \emph{sharp measure zero} sets that parallels Borel's \emph{strong measure zero}, and prove a theorem analogous to Galvin-Myscielski-Solovay Theorem, namely that a set of reals has sharp measure zero if and only if it is meager-additive. Some consequences: A subset of $2^ω$ is meager-additive if and only if it is $\mathcal E$-additive; if $f:2^ω\to2^ω$ is continuous and $X$ is meager-additive, then so is $f(X)$.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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